Alright well I want to buy a call cause I think the merger will go through, but if I buy it now, and then the merger goes through, the next day is the IV gunna plummet and screw me like CSCO did?

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You are missing a key point. You did not get screwed on the CSCO calls, you bought OTM of puts on CSCO which were $2 -$3 away from the strike with a week to expiration left. The IV change was minimal.

Before I would advise you on SIRI calls, I think you really need to understand why your OTM, (in this case 10% OTM!!!) puts lost money a week before expiration when the stock did not drop to your strike. Once you understand that process of deltas and time decay before expiration then you can tackle IV. Then you got the framework for understanding how options work to make better investments decisions.

Your first step to knowledge is to realize that you did not get screwed by CSCO puts. They did exactly what they were supposed to do given the movementin CSCO. YOU, and YOU alone take responsibility for your investment decisions and knowledge of how options work. From there you can learn a lot better.

IV collapse is not your only consideration. The stock has to move for you to profit on this calls if IV drops depending on the strike.

And as the point was made before, buy the stock, it is $3 and change. A perfect $0 strike call with no time value premium or vega risk and a delta of 1.00.